The role of the Montreal Cognitive Assessment (MoCA) and its memory tasks for detecting mild cognitive impairment

To investigate the role of the Montreal Cognitive Assessment (MoCA) (Beijing version) and its memory tasks on detecting different mild cognitive impairment (MCI) subtypes including amnestic MCI (aMCI) and nonamnestic MCI (naMCI) in memory clinics. A total of 121 patients with MCI and 53 healthy controls were included. Fifty-six aMCI-multiple domains (amMCI), 32 aMCI-single domain (asMCI), and 33 naMCI patients were diagnosed according to extensive cognitive tests. All participants were administered by the Mini Mental State Examination (MMSE) and the MoCA. Patients with amMCI performed worse than patients with asMCI, naMCI, and healthy controls on the MMSE and the MoCA (p <?0.001). The area under the curve (AUC) value for the MoCA when comparing the amMCI and control groups was 0.884 (p?<?0.001), which was superior to that of the MMSE. The AUC value decreased to 0.687 when applied to the naMCI and control groups (p?=?0.007), which was still higher than that of the Rey Auditory Verbal Learning Test (RAVLT) or the Rey-Osterrieth complex figure (ROCF). Delayed free recall or category prompted recall in the MoCA had roles in differentiating asMCI and controls groups with AUC value of 0.717 (p =?0.002) and 0.691 (p =?0.005), respectively. The MoCA is a good screening tool for detecting different types of MCI and is suitable for patients in outpatient clinics.     

Aβ and cognitive change: Examining the preclinical and prodromal stages of Alzheimer's disease

BackgroundHigh β-amyloid (Aβ) is associated with faster memory decline in healthy individuals and adults with mild cognitive impairment (MCI). However, longer prospective studies are required to determine if Aβ-related memory decline continues and whether it is associated with increased rate of disease progression.MethodsHealthy controls (HCs; n = 177) and adults with MCI (n = 48) underwent neuroimaging for Aβ and cognitive assessment at baseline. Cognition was reassessed 18 and 36 months later.ResultsCompared with low-Aβ HCs, high-Aβ HC and MCI groups showed moderate decline in episodic and working memory over 36 months. Those with MCI with low Aβ did not show any cognitive decline. Rates of disease progression were increased in the high-Aβ HC and MCI groups.ConclusionsIn healthy individuals, high Aβ likely indicates that Alzheimer's disease (AD)-related neurodegeneration has begun. Once commenced, the rate of decline in cognitive function remains constant across the preclinical and prodromal stages of AD.     

Cognitive impairment 3 years after neurological Varicella-zoster virus infection: a long-term case control study

Varicella-zoster virus (VZV) is one of the most common viruses causing central nervous system (CNS) infection, sometimes with severe neurological complications and sequelae despite appropriate antiviral treatment. Whether the neurological sequelae of VZV CNS infections include long-term cognitive impairment and how this impairment might affect the patients is still largely unknown. In this study, 14 patients with predominant CNS manifestations caused by VZV infection underwent cognitive testing 3 years (median 39.5 months, range 31–52 months) after acute disease. The results were compared with those for 28 controls, matched for age and gender. The tests covered the cognitive domains of speed and attention, memory and learning, visuospatial function, language and executive function. To further assess the cognitive dysfunction caused by neurological VZV infection, patients were classified into the concept of mild cognitive impairment (MCI), which is associated with development of dementia in other pathologies. The VZV patients performed significantly worse than controls on four tests covering the domains of speed and attention, memory and learning and executive function. The cut-off was set at 1.5 SD below mean age. In addition, a greater proportion of VZV patients were classified with MCI as compared with controls. In conclusion, patients with previous VZV infection affecting the brain had signs of long-term cognitive impairment in the domains of speed and attention, memory and learning and executive function. However, larger study populations are needed to confirm these results.     

Long-term cognitive outcome of bilateral subthalamic deep brain stimulation in Parkinson’s disease

The effect of subthalamic deep brain stimulation (STN DBS) on cognition in Parkinson’s disease (PD) remains controversial, and it is unclear which factors are related to cognitive decline and dementia after STN DBS, especially over the long term. To this end, we analyzed the cognitive outcome of 103 non-demented patients with PD who were followed-up for at least 12 months after bilateral STN DBS surgery. Preoperatively, the patients were evaluated with the Unified Parkinson's Disease Rating Scale and neuropsychological tests. The rate of global cognitive decline and the incidence of dementia during follow-up for up to 7 years (mean 42.4 ± 24.5 months) were calculated, and preoperative clinical and neuropsychological factors associated with postoperative global cognitive decline or dementia were analyzed. The prevalence of mild cognitive impairment (MCI) and its relation to later cognitive decline or dementia were also evaluated. The annual decline in the mini–mental state examination score was 0.4 ± 1.7 with impaired attention and executive function and a higher levodopa equivalent dose at baseline being the predictors of a faster global cognitive decline after STN DBS. Dementia developed in 13 patients with an incidence rate of 35.7 per 1,000 person-years. Impaired executive function at baseline predicted dementia. At baseline, 63.1 % of the patients had PD-MCI, and these patients were more likely to develop dementia than those without PD-MCI. This study showed that dysfunctions in the frontostriatal circuitry at baseline were associated with a risk of subsequent global cognitive decline and dementia in patients with PD who underwent STN DBS. In addition, preoperative PD-MCI was a risk factor for dementia after STN DBS.     

Cognitive profiles in Alzheimer's disease and in mild cognitive impairment of different etiologies

There has been increasing interest in determining whether amnestic, nonamnestic and multiple-domain subtypes of mild cognitive impairment (MCI) reflect different disease etiologies. In this study, we examined the extent to which cognitive profiles of nondemented patients with MCI diagnosed with prodromal Alzheimer's disease (AD) differed from those MCI patients diagnosed with vascular disease. We also compared these diagnostic groups to mildly demented patients diagnosed with AD and normal elderly controls. Results indicate that a majority of both MCI-AD and MCI-vascular patients experienced amnestic features and that multiple-domain was the most common presentation. MCI-AD and MCI-vascular groups did not differ on neuropsychological measures tapping memory, language, visuospatial skills/praxis or executive function. Further both MCI groups could be distinguished from dementia patients with regards to performance on measures of memory but not on non-memory measures. Considerable variability was observed in the degree of memory impairment among MCI patients with scores as much as 6 standard deviations below expected mean values. MCI-AD and MCI-vascular patients frequently exhibit both common and overlapping amnestic and nonamnestic features. The implication of these findings for future clinical research is discussed.     

The Alzheimer’s Disease Assessment Scale-Cognitive-Plus (ADAS-Cog-Plus): an expansion of the ADAS-Cog to improve responsiveness in MCI

Background

The Alzheimer’s Disease Assessment Scale cognitive subscale (ADAS-Cog) is widely used in AD, but may be less responsive to change when used in people with mild cognitive impairment (MCI).

Methods

Participants from the Alzheimer’s Disease Neuroimaging Initiative were administered a neuropsychological battery and 1.5 T MRI scans over 2–3 years. Informants were queried regarding functional impairments. Some participants had lumbar punctures to obtain cerebrospinal fluid (CSF). We added executive functioning (EF) and functional ability (FA) items to the ADAS-Cog to generate candidate augmented measures. We calibrated these candidates using baseline data (n?=?811) and selected the best candidate that added EF items alone and that added EF and FA items. We selected candidates based on their responsiveness over three years in a training sample of participants with MCI (n?=?160). We compared traditional ADAS-Cog scores with the two candidates based on their responsiveness in a validation sample of participants with MCI (n?=?234), ability to predict conversion to dementia (n?=?394), strength of association with baseline MRI (n?=?394) and CSF biomarkers (n?=?193).

Results

The selected EF candidate added category fluency (ADAS Plus EF), and the selected EF and FA candidate added category fluency, Digit Symbol, Trail Making, and five items from the Functional Assessment Questionnaire (ADAS Plus EF&FA). The ADAS Plus EF& FA performed as well as or better than traditional ADAS-Cog scores.

Conclusion

Adding EF and FA items to the ADAS-Cog may improve responsiveness among people with MCI without impairing validity.     

Relationship between baseline brain metabolism measured using [18F]FDG PET and memory and executive function in prodromal and early Alzheimer’s disease

Differences in brain metabolism as measured by FDG-PET in prodromal and early Alzheimer’s disease (AD) have been consistently observed, with a characteristic parietotemporal hypometabolic pattern. However, exploration of brain metabolic correlates of more nuanced measures of cognitive function has been rare, particularly in larger samples. We analyzed the relationship between resting brain metabolism and memory and executive functioning within diagnostic group on a voxel-wise basis in 86 people with AD, 185 people with mild cognitive impairment (MCI), and 86 healthy controls (HC) from the Alzheimer’s Disease Neuroimaging Initiative (ADNI). We found positive associations within AD and MCI but not in HC. For MCI and AD, impaired executive functioning was associated with reduced parietotemporal metabolism, suggesting a pattern consistent with known AD-related hypometabolism. These associations suggest that decreased metabolic activity in the parietal and temporal lobes may underlie the executive function deficits in AD and MCI. For memory, hypometabolism in similar regions of the parietal and temporal lobes were significantly associated with reduced performance in the MCI group. However, for the AD group, memory performance was significantly associated with metabolism in frontal and orbitofrontal areas, suggesting the possibility of compensatory metabolic activity in these areas. Overall, the associations between brain metabolism and cognition in this study suggest the importance of parietal and temporal lobar regions in memory and executive function in the early stages of disease and an increased importance of frontal regions for memory with increasing impairment.     

Voxel and surface-based topography of memory and executive deficits in mild cognitive impairment and Alzheimer’s disease

Mild cognitive impairment (MCI) and Alzheimer’s disease (AD) are associated with a progressive loss of cognitive abilities. In the present report, we assessed the relationship of memory and executive function with brain structure in a sample of 810 Alzheimer’s Disease Neuroimaging Initiative (ADNI) participants, including 188 AD, 396 MCI, and 226 healthy older adults (HC). Composite scores of memory (ADNI-Mem) and executive function (ADNI-Exec) were generated by applying modern psychometric theory to item-level data from ADNI’s neuropsychological battery. We performed voxel-based morphometry (VBM) and surface-based association (SurfStat) analyses to evaluate relationships of ADNI-Mem and ADNI-Exec with grey matter (GM) density and cortical thickness across the whole brain in the combined sample and within diagnostic groups. We observed strong associations between ADNI-Mem and medial and lateral temporal lobe atrophy. Lower ADNI-Exec scores were associated with advanced GM and cortical atrophy across broadly distributed regions, most impressively in the bilateral parietal and temporal lobes. We also evaluated ADNI-Exec adjusted for ADNI-Mem, and found associations with GM density and cortical thickness primarily in the bilateral parietal, temporal, and frontal lobes. Within-group analyses suggest these associations are strongest in patients with MCI and AD. The present study provides insight into the spatially unbiased associations between brain atrophy and memory and executive function, and underscores the importance of structural brain changes in early cognitive decline.     

Functional reorganization during cognitive function tasks in patients with amyotrophic lateral sclerosis

Cognitive deficits, especially in the domains of social cognition and executive function including verbal fluency, are common in amyotrophic lateral sclerosis (ALS) patients. There is yet sparse understanding of pathogenesis of the underlying, possibly adaptive, cortical patterns. To address this issue, 65 patients with ALS and 33 age-, gender- and education-matched healthy controls were tested on cognitive and behavioral deficits with the Edinburgh Cognitive and Behavioural ALS Screen (ECAS). Using functional magnetic resonance imaging (fMRI), cortical activity during social cognition and executive function tasks (theory of mind, verbal fluency, alternation) adapted from the ECAS was determined in a 3 Tesla scanner. Compared to healthy controls, ALS patients performed worse in the ECAS overall (p < 0.001) and in all of its subdomains (p < 0.02), except memory. Imaging revealed altered cortical activation during all tasks, with patients consistently showing a hyperactivation in relevant brain areas compared to healthy controls. Additionally, cognitively high performing ALS patients consistently exhibited more activation in frontal brain areas than low performing patients and behaviorally unimpaired patients presented with more neuronal activity in orbitofrontal areas than behaviorally impaired patients. In conclusion, hyperactivation in fMRI cognitive tasks seems to represent an early adaptive process to overcome neuronal cell loss in relevant brain areas. The hereby presented cortical pattern change might suggest that, once this loss passes a critical threshold and no cortical buffering is possible, clinical representation of cognitive and behavioral impairment evolves. Future studies might shed light on the pattern of cortical pattern change in the course of ALS.     

Confirmatory factor analysis of the ADNI neuropsychological battery

The Alzheimer’s Disease Neuroimaging Initiative (ADNI) is a large multi-center study designed to develop optimized methods for acquiring longitudinal neuroimaging, cognitive, and biomarker measures of AD progression in a large cohort of patients with Alzheimer’s disease (AD), patients with Mild Cognitive Impairment, and healthy controls. Detailed neuropsychological testing was conducted on all participants. We examined the factor structure of the ADNI Neuropsychological Battery across older adults with differing levels of clinical AD severity based on the Clinical Dementia Rating Scale (CDR). Confirmatory factor analysis (CFA) of 23 variables from 10 neuropsychological tests resulted in five factors (memory, language, visuospatial functioning, attention, and executive function/processing speed) that were invariant across levels of cognitive impairment. Thus, these five factors can be used as indicators of cognitive function in older adults who are participants in ADNI.     

图片学习测验在识别老年人轻微认知功能损害中的作用

目的　分析图片学习测验在识别老年人轻微认知功能损害 (MCI)中的作用。方法　选择符合MCI诊断标准的老年人 4 8例与正常对照组 5 6名完成图片学习测验、简易智能状态检查、听觉词语学习测验及多种非记忆测验。结果　图片学习测验的 3个记忆指标 (图片短时记忆、延迟记忆和学习记忆 )在MCI与正常对照组之间有非常显著的差异。已经给出这三个图片记忆指标区分MCI与正常老年人的划界分、敏感性和特异性。结论　图片记忆操作简便、信度和效度好 ,可以作为临床医师筛选MCI的有效工具     

A composite score for executive functioning, validated in Alzheimer’s Disease Neuroimaging Initiative (ADNI) participants with baseline mild cognitive impairment

The Alzheimer’s Disease Neuroimaging Initiative (ADNI) measures abilities broadly related to executive function (EF), including WAIS-R Digit Symbol Substitution, Digit Span Backwards, Trails A and B, Category Fluency, and Clock Drawing. This study investigates whether a composite executive function measure based on these multiple indicators has better psychometric characteristics than the widely used individual components. We applied item response theory methods to 800 ADNI participants to derive an EF composite score (ADNI-EF) from the above measures. We then compared ADNI-EF with component measures in 390 longitudinally-followed participants with mild cognitive impairment (MCI) with respect to: (1) Ability to detect change over time; (2) Ability to predict conversion to dementia; (3) Strength of cross-sectional association with MRI-derived measures of structures involved in frontal systems, and (4) Strength of baseline association with cerebrospinal fluid (CSF) levels of amyloid β_1-42, total tau, and phosphorylated tau_181P. ADNI-EF showed the greatest change over time, followed closely by Category Fluency. ADNI-EF needed a 40 % smaller sample size to detect change. ADNI-EF was the strongest predictor of AD conversion. ADNI-EF was the only measure significantly associated with all the MRI regions, though other measures were more strongly associated in a few of the regions. ADNI-EF was associated with all the CSF measures. ADNI-EF appears to be a useful composite measure of EF in MCI, as good as or better than any of its composite parts. This study demonstrates an approach to developing a psychometrically sophisticated composite score from commonly-used tests.     

Quality of life in patients with mild cognitive impairment

Background: Quality of life (QoL) is affected in patients with dementia, but it is not clear whether it is already disturbed in more initial phases of cognitive decline, like Mild Cognitive Impairment (MCI).

Aim: Compare the QoL in MCI patients with controls without cognitive impairment, and ascertain whether there are differences in the reports of QoL made by the subjects and by their informants.

Methods: Two hundred participants were enrolled, divided into MCI patients (n?=?50), MCI informants (n?=?50), recruited from a memory clinic and a dementia outpatient clinic, and controls (n?=?50) and controls informants (n?=?50), recruited in a family practice clinic. QoL was assessed with the QoL in Alzheimer disease (QOL-AD) scale.

Results: The total scores of the QOL-AD questionnaire were 32.1?±?6.9 for MCI patients self-report, 27.2?±?6.7 for MCI patients in the opinion of their informants, 35.3?±?4.9 for controls self-report and 35.6?±?4.9 for controls in the opinion of their informants. MCI patients had lower QOL-AD scores than controls. The QoL reported by patients with MCI was more favorable than the opinion of their informants.

Conclusion: The QoL is affected at early stages of cognitive decline. The QoL reported by patients with MCI is better than the opinion of their informants, similarly to what is known in Alzheimer's disease patients. QoL appears to be an important domain to be evaluated in aging studies.     

轻度认知功能障碍患者的神经心理学研究

目的 探讨轻度认知功能障碍(MCI)患者神经心理学的特点. 方法 对42例MCI患者和55例健康对照者进行多项神经心理学检查,包括简易精神状态检查量表(MMSE)、蒙特利尔认知评估量表(MoCA)、临床痴呆评定量表(CDR)、语言流畅性测验(RVR)、韦氏智力测验(WAIS-RC)[包括数字广度测验(DS)、积木测验(BD)、相似性测验]、韦氏记忆测验(WMS-R)(包括逻辑记忆、联想学习、视觉再认、图片回忆)、日常生活能力量表(ADL),比较2组患者上述量表评分和MMSE、MoCA量表各亚项评分的差异.结果 与对照者比较,MCI患者MMSE、MoCA总分和RVR、WAIS-RC、WMS-R分测验,MoCA量表各亚项(地点定向力除外),MMSE量表中计算与注意、延迟回忆两亚项评分较低,差异均有统计学意义(P<0.05).结论 MCI患者不仅记忆受损,其计算与注意力、命名、视空间结构能力、执行功能也可受损,尤以延迟回忆、计算与注意力受损明显.MoCA涵盖了重要的认知领域,能较全面评估MCI患者的认知功能,值的临床推广应用.     

Prospective memory in idiopathic REM sleep behavior disorder with or without mild cognitive impairment: A preliminary study

Objective: The ability to execute delayed intentions, known as prospective memory (PM), is crucial to everyday living. PM failures are reported in mild cognitive impairment (MCI) and Parkinson’s disease, however, no study to date has investigated PM functioning in individuals at high risk of developing these conditions, precisely those diagnosed with idiopathic REM sleep behavior disorder (iRBD). We aimed to assess PM in iRBD according to patients’ cognitive status and to determine the underlying nature of their difficulties. Method: Fifty-eight participants, including 20 healthy controls (HC) and 38 polysomnographic-confirmed iRBD patients with (iRBD-MCI = 13) or without (iRBD-nMCI = 25) MCI participated in this study. Following a neuropsychological assessment, PM was evaluated using a self-administered questionnaire (PRMQ), a simple clinical measure (envelope test), and a laboratory cue salience task. Results: No significant group differences were noted on the PRMQ and envelope test. On the PM laboratory task, non-parametric analyses revealed better detection accuracy in HC than both iRBD groups for all high and low salient cues. While iRBD-nMCI and iRBD-MCI patients performed similarly on the high salient condition, the latter showed significant difficulty in detecting low salient cues. Multiple regression analyses revealed executive dysfunction as the best predictor to significantly account for differences in the low salient condition in iRBD. Conclusion: PM difficulties in iRBD are most important in patients with MCI (vs without MCI) and may be attributed to a gradual alteration in executive mechanisms. PM impairment could act as a promising indicator of early cognitive dysfunction in iRBD.     

Cognitive dysfunction in adult patients with neuromyelitis optica: a systematic review and meta-analysis

The objective of this study was to investigate cognitive dysfunction in 24–60-year-old neuromyelitis optica (NMO) patients, demographically matched healthy subjects, and MS patients. We conducted a comprehensive literature review of the PubMed, Medline, EMBASE, CNKI, Wan Fang Date, Web of Science, and Cochrane Library databases from inception to May 2016 for case–control studies that reported cognitive test scores in NMO patients, healthy subjects, and MS patients. Outcome measures were cognitive function evaluations, including performance on attention, language, memory, information processing speed, and executive function tests. The meta-analysis included eight studies. NMO patients performed significantly worse on attention (P < 0.00001), language (P = 0.00008), memory (P = 0.00004), information processing speed (P < 0.00001), and executive function tests (P = 0.00009) than healthy subjects. There were no significant differences in performance between NMO patients and MS patients on these tests. This meta-analysis indicates that NMO patients aged 24–60 years have significantly worse cognitive performance than demographically matched healthy subjects. However, this was comparable to the performance of demographically matched MS patients. There is a need for further rigorous randomized controlled trials with focus on elucidating the underlying mechanism of cognitive dysfunction in NMO patients.     

Mild parkinsonian signs and psycho-behavioral symptoms in subjects with mild cognitive impairment

BACKGROUND: Mild cognitive impairment (MCI) may be accompanied by extra pyramidal signs (EPS), which are related to the severity and type of cognitive impairment. We aimed to elucidate further the relationship between MCI and EPS, analyzing the correlation between the severity of EPS and cognitive functions, and the presence of EPS and neuro-psychiatric features. METHODS: Data were obtained from a longitudinal study of 150 MCI outpatients. Participants underwent a clinical assessment including the Unified Parkinson Disease Rating Scale, the Neuropsychiatric Inventory, the Tinetti Scale, and a standardized neuropsychological battery. Mild EPS could be defined as being present (MCI with mild EPS) using a subscale of UPDRS, based on three specific symptoms: bradykinesia, rigidity and tremor. RESULTS: The two groups, one with mild EPS (24%) and one without EPS (76%), differed in gait abnormalities and presence of extrapyramidal symptoms. Groups did not differ in terms of general cognitive functions evaluated using the Mini-mental State Examination, while subjects with MCI with mild EPS performed significantly worse than those with MCI without EPS in total global score and in non-memory items of the Alzheimer's Disease Assessment Scale. Moreover, severity of EPS was significantly correlated with low performance on executive functions and with high performance on episodic memory. The group with MCI with mild EPS were observed to have a greater prevalence of patients with anxiety, depression, apathy and sleep disturbances than in MCI without EPS. CONCLUSION: MCI may be associated with mild parkinsonian signs, the severity of which are related to the severity of cognitive impairment, in particular of non-memory functions, and to a differential pattern of psycho-behavioral symptoms.     

Diffusion tensor imaging (DTI) in the detection of white matter lesions in patients with mild cognitive impairment (MCI)

Mild cognitive impairment (MCI) is recognized as a precursor to dementia. The amnestic MCI progresses usually to Alzheimer disease. Amnestic MCI multiple domain (md-MCI) seems to progress more rapidly than amnestic MCI single domain (a-MCI). In an attempt to identify patients at risk, we examined white matter changes in MCI subtypes using diffusion tensor imaging (DTI). We also tried to correlate DTI findings to neuropsychological tests. Forty-four amnestic single domain (a-MCI) patients, 19 amnestic multi domain (md-MCI), and 25 cognitively normal (NC) controls were included in the present study. All participants were assessed clinically using a battery of cognitive tests. DTI was performed to measure fractional anisotropy (FA) and apparent diffusion coefficient (ADC). Areas studied were corpus callosum, posterior cingulum (PC), anterior cingulum (AC), and superior longitudinal fasciculus (SLF). ADC and FA of the above areas were related to the scores of certain neuropsychological tests that evaluate visual and verbal memory. No difference in DTI measurements was found between the two MCI subtypes. ADC in MCI cases was increased in comparison with NC in the genu, PC, right SLF, and left AC. FA was spared. Verbal memory was related to ADC of the genu, PC, right AC and right SLF, and to FA of the left SLF. Visual memory was related to ADC of the genu, PC, right AC, and SLF. The strongest correlation found was between the visual memory and the ADC of the right PC (Spearman ρ = 0.45, p < 0.001). DTI revealed that ADC was increased in certain brain areas in MCI patients. No difference in DTI measurements was found between the two MCI subtypes. DTI indices correlate with cognitive performance.     

Clinical core of the Alzheimer's disease neuroimaging initiative: Progress and plans

The Clinical Core of the Alzheimer's Disease Neuroimaging Initiative (ADNI) has provided clinical, operational, and data management support to ADNI since its inception. This article reviews the activities and accomplishments of the core in support of ADNI aims. These include the enrollment and follow-up of more than 800 subjects in the three original cohorts: healthy controls, amnestic mild cognitive impairment (now referred to as late MCI, or LMCI), and mild Alzheimer's disease (AD) in the first phase of ADNI (ADNI 1), with baseline longitudinal, clinical, and cognitive assessments. These data, when combined with genetic, neuroimaging, and cerebrospinal fluid measures, have provided important insights into the neurobiology of the AD spectrum. Furthermore, these data have facilitated the development of novel clinical trial designs. ADNI has recently been extended with funding from an NIH Grand Opportunities (GO) award, and the new ADNI GO phase has been launched; this includes the enrollment of a new cohort, called early MCI, with milder episodic memory impairment than the LMCI group. An application for a further 5 years of ADNI funding (ADNI 2) was recently submitted. This funding would support ongoing follow-up of the original ADNI 1 and ADNI GO cohorts, as well as additional recruitment into all categories. The resulting data would provide valuable data on the earliest stages of AD, and support the development of interventions in these critically important populations.     

轻度认知功能障碍患者的执行功能和工作记忆研究

目的 了解轻度认知功能障碍(MO)患者的执行功能和工作记忆是否损害及工作记忆损害特点,探讨执行功能对MCI患者的日常生活活动能力(ADL)的影响.方法 运用神经心理学测试的方法对30例MCI患者进行执行功能、工作记忆及其他认知功能检查,同时进行ADL评定,另外选择30名健康老人作为对照组.结果 MCI组的执行功能和工作记忆成绩(分)显著低于对照组,其中数字颜色连线干扰(130.8±58.2)、数字颜色连线B(210.2±81.8)、词汇流畅性测试(8.9±5.4)、视觉客体工作记忆(0.73±0.12)和数字广度(3.4±0.9),除视觉空间工作记忆外,与对照组比较(52.0±13.5、121.0±33.4、16.4±5.4、0.85±9.18、4.2±1.1)差异均有统计学意义(t=7.108、5.159、-4.879、-4.351、-2.544,均P<0.01或P<0.05).用多元逐步回归方法分析执行功能对ADL的影响,结果 客体工作记忆、空间工作记忆和词汇流畅性与ADL的影响相关,而客体工作记忆与ADL的影响有显著相关性(β=-0.720,t=-3.571,P=0.001).结论 MCI患者具有明显的执行功能障碍和工作记忆损害,工作记忆与MCI患者的ADL有良好相关性,而且视觉客体工作记忆与MCI患者的ADL测查具有显著相关性,因此MCI患者的执行功能障碍可能是导致其ADL下降和客体工作记忆损害的主要因素.